/*!
 * jquery.tagcloud.js
 * A Simple Tag Cloud Plugin for JQuery
 *
 * https://github.com/addywaddy/jquery.tagcloud.js
 * created by Adam Groves
 */
(function($) {

    /*global jQuery*/
    "use strict";

    var compareWeights = function(a, b)
    {
        return a - b;
    };

    // Converts hex to an RGB array
    var toRGB = function(code) {
        if (code.length === 4) {
            code = code.replace(/(\w)(\w)(\w)/gi, "\$1\$1\$2\$2\$3\$3");
        }
        var hex = /(\w{2})(\w{2})(\w{2})/.exec(code);
        return [parseInt(hex[1], 16), parseInt(hex[2], 16), parseInt(hex[3], 16)];
    };

    // Converts an RGB array to hex
    var toHex = function(ary) {
        return "#" + jQuery.map(ary, function(i) {
            var hex =  i.toString(16);
            hex = (hex.length === 1) ? "0" + hex : hex;
            return hex;
        }).join("");
    };

    var colorIncrement = function(color, range) {
        return jQuery.map(toRGB(color.end), function(n, i) {
            return (n - toRGB(color.start)[i])/range;
        });
    };

    var tagColor = function(color, increment, weighting) {
        var rgb = jQuery.map(toRGB(color.start), function(n, i) {
            var ref = Math.round(n + (increment[i] * weighting));
            if (ref > 255) {
                ref = 255;
            } else {
                if (ref < 0) {
                    ref = 0;
                }
            }
            return ref;
        });
        return toHex(rgb);
    };

    $.fn.tagcloud = function(options) {

        var opts = $.extend({}, $.fn.tagcloud.defaults, options);
        var tagWeights = this.map(function(){
            return $(this).attr("rel");
        });
        tagWeights = jQuery.makeArray(tagWeights).sort(compareWeights);
        var lowest = tagWeights[0];
        var highest = tagWeights.pop();
        var range = highest - lowest;
        if(range === 0) {range = 1;}
        // Sizes
        var fontIncr, colorIncr;
        if (opts.size) {
            fontIncr = (opts.size.end - opts.size.start)/range;
        }
        // Colors
        if (opts.color) {
            colorIncr = colorIncrement (opts.color, range);
        }
        return this.each(function() {
            var weighting = $(this).attr("rel") - lowest;
            if (opts.size) {
                $(this).css({"font-size": opts.size.start + (weighting * fontIncr) + opts.size.unit});
            }
            if (opts.color) {
                $(this).css({"color": tagColor(opts.color, colorIncr, weighting)});
            }
        });
    };

    $.fn.tagcloud.defaults = {
        size: {start: 14, end: 18, unit: "pt"}
    };

})(jQuery);